The present invention relates to a compressed-air nail firing tool.
It is known to use compressed-air nail firing tools which are adapted to fire metal nails, for example for fixing wood items and the like. Said nail firing tools are substantially constituted by a body which lies above a handle which can be connected to a compressed air delivery hose; means for the actuation of a striking blade in a piston-like fashion are accommodated inside said body. The striking blade is adapted to engage a firing channel formed along a tube which protrudes from a head which is fixed in a front region to the nail firing tool body.
The nails to be fired are fed sequentially to the firing channel from a magazine which is rigidly coupled to the nail firing tool, below the tube, inside which a ribbon of nails, rolled into a reel, is loaded. The nails are mutually parallel along said ribbon on an axis which is substantially transverse to the longitudinal extension of the belt.
The nails are fed individually to the firing channel under the control of an advancement device which is associated with the magazine. In practice, the device actuates the stepwise advancement of the ribbon of nails loaded in the magazine, placing the first nail of the ribbon at the firing channel, where the nail is struck forcefully by the striking mass.
The nail ribbons used with the above described nail firing tools are currently manufactured in various ways.
In particular, in the case of roundhead nails, ribbons are known which are constituted by a strip of plastics which is shaped so as to form a series of clips which are adapted to retain the nails. As shown by way of example in FIG. 5, the nails 10 are retained by the strip 12 proximate to the respective head 11; the strip 12 forms the clips 13, which individually retain the nails 10 in two appropriately spaced points.
According to another conventional solution, the nails are mutually rigidly coupled by two thin metal wires which are soldered on one side of said nails.
The nail ribbon must be guided appropriately in the magazine of the nail firing tool, particularly at the region for feeding the nails to the firing channel formed by the tube.
For this purpose, if ribbons of nails retained by a strip of plastics are used, the magazine is provided internally for example with a slotted guide in which the strip of plastics is slidingly inserted.
If instead ribbons of nails retained by two soldered metal wires are used, the metal wires slide inside corresponding grooves formed by the magazine.
In order to use both types of nail ribbon it is therefore necessary to use suitable adaptors, such as for example removable guides to be applied to the magazine if the ribbons of nails retained by a strip of plastics are used.
This of course makes the structure of the nail firing tool more complicated, with a greater risk of breakage and abnormal operation, and also makes the nail firing tool more difficult to use if it is necessary to change the type of nail ribbon.